The present invention concerns a cargo holding device such as a container, pallet or similar, in particular for loading aircraft, and a method for production of a cargo holding device.
Cargo containers and freight pallets—i.e. cargo holding devices—are essential for effective transport of loads in aircraft as they allow rapid loading and unloading of the aircraft. The great majority of commercial aircraft can receive a multiplicity of cargo containers or freight pallets. Most containers or pallets are standardised so they can be used irrespective of the aircraft used for their transport. Until ten years ago, cargo containers were made exclusively of aluminium, wherein the own weight of the container was around 100 kg. Some containers used at present partly comprise lighter materials so that now, cargo containers with a weight of around 60 kg are used. Reducing the own weight of such containers or pallets is extremely important. A cargo container is described for example in DE 20 64 241. The use of non-metallic materials (see DE 696 16 182 T2) in this context has also been considered. DE 696 16 182 T2 proposes for example a cargo container which has a frame of an aluminium alloy in which side walls and a roof of fibre-reinforced plastic are inserted.
DE 34 09 683 A1 describes a cargo container which is made in the manner of a frame. The frame comprises hollow profiles which are connected together via corner connectors. The hollow profiles are pushed onto pin-like arms of the corner connectors. The frame assembly is not described in detail in DE 34 09 683 A1. Because of the formation of the corner connectors and hollow profiles however, it can be assumed that assembly is comparatively complex and in particular entails a bending or deforming of the hollow profiles, at least when the frame is closed.
Starting from said prior art, the object of the present invention is to provide an improved cargo holding device. In particular the production costs and production complexity of the cargo holding device should be reduced and the functionality (e.g. ease of handling) and stability increased. In particular, a frame construction is proposed which can be assembled in a simple manner.
This object is achieved by a cargo holding device according to claim 1. In particular the object is achieved by a cargo holding device, e.g. a cargo container or pallet, for loading aircraft, comprising a bottom element, several profile elements and (separate) corner elements, wherein a bottom element edge portion and/or an edge portion of a side wall is connected to the profile element and corner elements, wherein several profile elements are connected to several corner elements via push-fit connections, wherein at least one push-fit connection comprises a push-fit connection recess and a corresponding push-fit connection pin such that the profile element and the corner element can be connected together by a translational movement, wherein a translational movement direction has an angle in relation to a profile longitudinal axis of the profile element.
An essential concept of the invention is that at least one profile element and corner element are matched to each other such that the profile element and the corner element can be connected together by push-fit, wherein a push movement runs obliquely to the profile longitudinal axis of the profile element. In DE 34 09 683 A1 for example, all profile elements and corner elements can also be attached to each other by push-fit, but because of the concrete design of the elements, only by means of a straight push movement, i.e. the profile element must be moved in relation to the corner element in a direction parallel to the profile longitudinal axis. As the applicant has found, this is because the ends of the profile elements run vertically to the profile longitudinal axis, and end faces of the connection pins of the corner connectors in DE 34 09 683 A1 also run vertically to the profile longitudinal axis (in mounted state). By forming the cargo holding device such that an oblique push movement is possible, the frame can be closed in a simpler manner, in particular no deformation or only a reduced deformation of one profile element (the last profile element) is required. As a result the material choice for the frame is less restricted and the frame as a whole is more stable. Also assembly is simplified in comparison with the prior art.
The push-fit connection pin is preferably an (integral) component of the profile element or corner element. The push-fit connection recess is preferably also an (integral) component of the corner element or profile element. Preferably the movement direction has an angle of greater than 0°, preferably greater than 30°, in particular (around) 40°-50°, for example 45°.
Preferably an inner edge portion of the push-fit connection pin is offset in the profile longitudinal direction in relation to an outer edge of the push-fit connection pin, and/or an inner edge portion of the push-fit connection recess is offset in the profile longitudinal direction in relation to an outer edge portion of the push-fit connection recess. With such an offset, it is possible particularly easily to insert for example the corner element in the profile element by an obliquely inwardly directed, translational movement.
A push-fit connection recess edge or a push-fit connection pin edge can at least in portions have an angle in relation to the profile longitudinal axis of less than 90°, preferably less than 60°, in particular 40°-50°, for example 45°. With such angles (for example an angle of 45°) it is possible particularly easily to move the corner element from the outside obliquely inwards (in the direction of a centre of the cargo holding device) and at the same time connect the corner element to the profile element via the push-fit connection. This reduces the complexity of assembly.
In a concrete embodiment, the push-fit connection recess is open towards the outside. Alternatively or additionally, the inner edge portion of the push-fit connection pin and the outer edge portion of the push-fit connection pin can be at the same height in relation to the profile longitudinal axis. The push-fit connection pin can therefore (in principle) be designed in the same way as in the prior art, namely in DE 34 09 683 A2. If the push-fit connection recess is open not only (as in the prior art) in the direction of the profile longitudinal axis but also (partially) towards the outside, the (conventional) corner connection pin can still be introduced obliquely into the push-fit connection recess.
In a preferred embodiment, the push-fit connection pin is an (integral) component of the corner element and the push-fit connection recess is an (integral) component of the profile element. With such an embodiment, the push-fit connection can be implemented particularly easily and the frame closed.
Preferably the push-fit connection pin is arranged on a pin base surface which runs at least in portions at an angle in relation to the profile longitudinal axis of preferably greater than 0°, preferably greater than 30°, in particular 40°-50°, for example 45°. In this refinement, an end face of the push-fit connection pin preferably runs in relation to the profile longitudinal axis such that the end face of the push-fit connection pin and the pin base surface have an angle to each other. In this embodiment, the pin base surface can serve as a stop surface for a push-fit connection recess edge. A pin base which defines the pin base surface can terminate flush with the profile element. This achieves a simple overall construction which is easy to produce.
Preferably the pin base surface stops on a push-fit connection recess edge. In particular the pin base surface borders the push-fit connection recess edge flush.
In a concrete embodiment, at least one bore is provided in the push-fit connection pin and in a connecting segment defining the push-fit connection recess, wherein the bores align with each other in mounted state. This further stabilises the connection without (substantially) increasing the overall complexity.
The object cited above is furthermore achieved in particular by a cargo holding device, in particular of the type described above, for example a cargo container or a pallet, in particular for loading aircraft, comprising a bottom plate, wherein an edge of the bottom plate and/or an edge portion of a side wall is connected to a plurality of profile elements, wherein the profile elements are connected together via a plurality of push-fit connections, wherein two adjacent profile elements each form a push-fit connection with a third (in the sense of a further) profile element only at their ends facing away from the respective other profile element.
A core concept of this cargo holding device is that a frame in which the bottom element can be received can be formed easily by connecting together a plurality of profile elements. The frame can be closed particularly simply by form fit thanks to the absence of a push-fit connection at two adjacent profile elements. In particular in combination with a hook construction as described further below, the bottom plate can be connected to the profile elements easily and reliably. As a whole, this allows a constructionally simple assembly or dismantling.
Preferably several corner elements are provided which are each connected to two profile elements via a push-fit connection, wherein an end corner element is provided which is connected to maximum one profile element via a push-fit connection. On assembly of the cargo holding device, a frame comprising the profile elements and corner elements can be constructed in a particularly simple manner, wherein because of the special configuration of the end corner element, the frame can easily be closed by form fit (without having to deform the frame). Thus the frame can be produced in a particularly simple manner.
In a concrete embodiment, several corner elements are provided with two push-fit connection pins, one of which can be inserted in a profile element, wherein an end corner element is provided which has maximum one push-fit connection pin.
The embodiment in which two adjacent profile elements form maximum one push-fit connection is preferred in particular in a cargo container. In particular, a corner element without connection pin (which fundamentally weakens the overall structure) can be compensated in that the entire cargo holding device is supported via a connection to further elements (for example vertical walls). Loads can be supported particularly favourably via a connection (bolting) to the vertical walls. In principle such a configuration can be used in a pallet (in which case a different form of connection may be required, for example bolting). However the solution described above is used for preference in a pallet in which the push-fit connection is configured such that an oblique movement direction is possible (when push-fitting together). There is no vertical element in a pallet. However the proposed push-fit connection allows a secure connection between two profiles (meeting at a 90° angle). There is no need for a costly bolted construction. In particular if the corner profiles are connected to the bottom plate by a clip connection, an (almost) bolt-free pallet is achieved, wherein a twisting of the profiles is prevented by the push-fit connection solution.
The object cited above is achieved independently by a cargo holding device, in particular of the type described above, for example a cargo container or pallet, in particular for loading aircraft, comprising a bottom element, profile elements and corner elements, with at least one push-fit connection pin, wherein the push-fit connection pin can be introduced into a corner element and/or into a profile element, wherein the push-fit connection pin is movable in relation to both the corner element and the profile element, in particular along the profile longitudinal direction. This moveability allows the push-fit connection pin for example to be removed or for example inserted in a corresponding push-fit connection recess. This makes the push-fit connection more variable. In particular a frame can be “closed” in a simple manner. Preferably the push-fit connection pin can be fixed (releasably) in relation to the profile element and/or corner element. The push-fit connection pin can thus be locked in relation to the profile element or corner element (for example by bores in the corner element or profile element, wherein a pin or a bolt can be introduced into the bores). Also a frame can be provided, wherein no further elements need be removed in order to exchange a profile or corner element (or further elements such as a wall or tarpaulin). For example an individual element (e.g. tarpaulin or profile element) can be removed from the cargo holding device independently.
In one embodiment, at least one corner element can be composed such that the bottom element edge portion and/or the side wall edge portion can be removed from the profile element, preferably in the direction towards the corner element, while the corner element is connected to at least one profile element. For this, the respective corner element can have a recess (e.g. a groove) which substantially links to the bottom receiving groove and/or side wall receiving groove, and continues the bottom receiving groove and/or side wall receiving groove such that the side wall/bottom element can be removed from the respective profile element while the corner element is connected. To this extent, the side walls and/or the bottom element can easily be removed without the need to dismantle the container completely. Preferably these corner elements are used where the side wall, for example in the form of a loading door or loading tarpaulin, is not connected to all profile elements via grooves. For example, a side wall/loading tarpaulin can be connected to just one profile element. Further connections can be made by hook and loop closure and/or via straps. The side wall/loading tarpaulin can be removed as required using the corner element outlined here.
The object cited above is achieved independently by a method for production of a cargo holding device, in particular a cargo container or pallet, preferably of the type described above, comprising at least one bottom element, several profile elements and several corner elements, wherein at least one profile element and at least one corner element are connected together by push-fit by a translational movement at an angle in relation to a profile longitudinal axis of at least 0°, preferably greater than 30°, in particular 40°-50°, for example 45°. This method features a simple process and results in a stable cargo holding device.
According to an independent concept, a method is proposed, preferably of the type described above, for production of a cargo holding device, in particular of the type described above, comprising at least one bottom element and a plurality of profile elements which are connected to an edge of the bottom element, wherein several profile elements are connected to both adjacent profile elements via a push-fit connection, wherein two adjacent end profile elements are each connected to a third (in the sense of further) profile element only at their ends facing away from each other.
The object above is furthermore achieved by a method, in particular of the type described above, for production of a cargo holding device, in particular of the type described above, comprising at least one bottom element and at least one profile element connected to the bottom element, wherein the bottom element and profile element are brought together at a first predefined angle and then hooked by rotation. With regard to the advantages of the method, reference is made to the cargo holding device described above.
This object is furthermore achieved by a cargo handling device according to this disclosure. In particular the object is achieved by a cargo holding device, preferably of the type described above, e.g. a cargo container or a pallet, in particular for loading aircraft, comprising at least one bottom element and at least one profile element which is connected to the bottom element, wherein at least one end portion of the bottom element is releasably connected to the at least one profile element via a connecting device comprising a hook.
An essential concept of this solution or refinement is that the bottom element can be attached to the profile element by the provision of a hook. This results in a constructionally simple but nonetheless secure connection. Assembly and dismantling of the cargo holding device are facilitated. In particular there is no need for an irreversible gluing or locking.
Preferably a connection can be created between the bottom element and the profile element via a push-fit (of the bottom and/or profile element) with subsequent rotation (of the bottom and profile element in relation to each other). Alternatively or additionally a connection between the bottom element and the profile element can be released via a rotation (of the bottom and profile element in relation to each other) with subsequent separation of the bottom and/or profile element from each other. As a whole, this allows a reliable connection which in particular facilitates assembly and dismantling. Even without the provision of an irreversible gluing or locking, the connection is comparatively reliable (in particular because of the provision of the hook).
In a concrete embodiment, the connection device comprises at least one groove and at least one tongue. The groove can for example be provided in the profile element (and/or in the bottom element). The tongue is preferably provided in the bottom element. Alternatively or additionally, at least one groove is provided in the profile element. Such a tongue and groove connection together with the hook allows extremely simple assembly/dismantling.
A cross-section of the groove and/or the tongue can be round, in particular circular, at least in portions. This allows the profile and bottom element to be rotated in relation to each other particularly easily, which facilitates assembly/dismantling. A cross-section of the groove is preferably completely circular (apart from the groove opening).
At least one tongue and/or at least one groove can be asymmetrical so that the tongue can be introduced into the groove at a predefined first relative angle thereto, and hooked into the groove at a predefined second relative angle (different from the first). In this embodiment, the groove and tongue are formed such that the tongue acts as a hook in the associated groove or is formed as a hook. This refinement is particularly simple in construction and allows a stable connection.
In particular if a cross-section of the groove (apart from a groove opening) is circular, a cross-section of the tongue can have a length (maximum length) in a longitudinal direction and a width (maximum width) in a width direction, wherein the longitudinal direction stands perpendicular to the width direction, wherein the length is greater than the width (for example at least 1.1 times or at least 1.3 times or at least 1.6 times as great). The connection to the groove can be made simply and securely with such an oblong (in cross-section) tongue.
Preferably a cross-section of the tongue has a circle arc portion and a rotation-support protrusion (fulcrum) opposite the circle arc portion. With such an embodiment, the tongue can be levered into the groove particularly easily by rotation, thus allowing assembly and dismantling.
Preferably an edge portion of the bottom plate and/or at least one profile element edge portion facing the edge portion of the bottom plate is hooked shaped (in cross-section). With corresponding formation of the edge, there is no need for a separate component (for example a separate hook). The connection can therefore be made constructionally extremely simply.
At least one bottom plate edge portion of the bottom plate can be bent inwards. Alternatively or additionally, at least one profile element edge portion facing the bottom plate edge portion can be chamfered downwards in the direction of the bottom plate. In an embodiment of the cargo holding device as a pallet, “inwards” can mean that the bend is oriented in the direction of a cargo holding surface. For a container, “inwards” can mean that the bend is oriented in the direction of a middle of the cargo holding space. In any case, this allows a stable and in particular form-fit design of the bottom. The material usage is here particularly low. The connection between the bottom element and the profile element is nonetheless reliable and secure.
The bottom plate and/or at least one, preferably pultruded, profile element can be made of fibre-reinforced carbon, at least in portions. This allows firstly a weight saving. In particular in the case of production by pultrusion, the advantage results that the hook construction is extremely stable against a tensile load from the bottom element thanks to the orientation of the fibres of the profile element along its longitudinal axis.
In a concrete refinement, at least one wall element and at least one profile element are fitted with a slot wherein an edge, in particular widened, preferably peripheral, of the wall element is or can be pushed into the slot. With such a design, tensile loads can be transmitted at right angles to an edge of the wall (tarpaulin) within one tarpaulin layer. By synergy effect in combination with the construction and assembly of the bottom element, this allows a simple but nonetheless stable construction of the entire cargo holding device. The wall element serves in a simple manner as a structural element for the entire cargo holding device. This allows an even lighter frame construction and the omission of separate connecting means, such as rivets and bolts.
Preferably at least one wall element is provided which has a stiffening element, in particular comprising an additional wall layer (tarpaulin layer), running from one wall corner to the diagonally opposite wall corner. Further preferably, stiffening elements run from all four wall corners to their diagonally opposite wall corners, so that as a whole a cross-shaped stiffening element is formed. The at least one stiffening element can be implemented by a (local) increase in the number of layers (number of tarpaulin layers). The stiffening elements allow tensile loads to be absorbed at corner points so that they need not (any longer) be dissipated via the frame profiles. In particular in combination with the bottom element described above, a construction is achieved which is extremely lightweight and simple to assemble. Any push-fit connections or hook connections provided are stabilised by the stiffening elements. With this measure, the at least one wall element becomes a structurally reinforcing element for the entire cargo holding device. This allows a lightweight construction (frame construction) and the omission of separate connecting means such as rivets and bolts.
According to a refinement which is also claimed independently, the object is also achieved by a cargo holding device such as a container, pallet or similar, in particular for loading aircraft, wherein the cargo holding device comprises at least one bottom element and at least one pultruded profile element of fibre-reinforced plastic.
An essential concept of this refinement or independent aspect is to use a profile element of fibre-reinforced plastic, which is produced in the pultrusion process (extrusion-drawing process), to stabilise the cargo holding device. Because of the pultrusion process, the profile element of fibre-reinforced plastic is given a resistance, in particular against a bending load, which cannot be achieved by conventional methods for processing fibre-reinforced plastic (for the same material usage). As a whole therefore a stable construction of a cargo holding device is possible with lower material usage. This means that the weight of a cargo holding device can be further reduced substantially. Furthermore an efficient production is ensured.
Preferably at least one profile element is formed as a hollow profile, at least in portions. This allows a further weight reduction for the same or increased stability.
At least one profile element can form at least one part of a frame of the cargo holding device, in particular of the bottom element. Forces which act on the frame in such a cargo holding device can be distributed to the frame particularly favourably thanks to the pultruded design of the profile element.
At least one profile element can comprise at least one fixing device, such as for example a push-fit device, in particular a preferably round groove or a rail, for fixing a wall element, in particular a bottom element and/or a lashing device. In particular a groove or rail can be produced in the pultrusion process at little cost. This offers a weight-saving possibility for connecting different wall elements to the profile element in a simple manner. In particular if the profile element is formed as part of a frame, the cargo holding device can be assembled, dismantled and repaired in a simple manner.
In concrete embodiments, the profile element can be connected with a further profile element and/or a corner element via a push-fit connection. In particular, the push-fit connection between two profile elements can be implemented via a corner element. The push-fit connection between two profile elements can however also be made directly such that the profile elements are in contact. Two or more profile elements can also be assembled into an extended profile element via one or more (straight) intermediate piece(s). Thus in a simple manner, various profile elements can be produced or the size of the cargo holding device can easily be adapted.
In a preferred embodiment, at least one corner element is provided for connection, in particular push-fit connection, of two profile elements. The at least one corner element can have at least one pin (extension) corresponding to a recess of the profile element. In the embodiment of the profile element as a hollow profile, the pin (extension) preferably corresponds in cross-section to the cross-section of a hollow chamber of the hollow profile. This again facilitates production of the cargo holding device.
Preferably at least one (in some cases, tarpaulin-like) wall, in particular a side wall or top, is produced at least in portions from a fibre-reinforced plastic. In conjunction with the pultruded profile elements, as a whole an extremely lightweight cargo holding device can be achieved with high stability.
At least one wall, in particular a bottom wall or a cargo floor, can comprise a core layer of fibre-reinforced plastic and a seating layer (support layer) of a metal, in particular an aluminium alloy, wherein the core layer and seating layer are joined together preferably by material fit. An essential concept of this embodiment is to reduce the weight, for example of the cargo floor, in that this is made in several layers, in particular in a sandwich construction, wherein materials of metal and plastic are used for the layers. The bottom wall can be constructed as explained in German patent application file ref. DE 10 2011 050 893.7 and/or produced accordingly. Materials of metal and plastic can be used for the layers. Predefined requirements, e.g. with regard to friction and wear behaviour, can be taken into account here, wherein as a whole a very stable composite material or laminate is produced.
Preferably the layers are joined together by material and/or form fit, where a material fit join leads to particularly good results.
Preferably the seating layer of metal alloy serves as an outer layer for the action of cargo drive units. Furthermore this layer absorbs spot loads and distributes them over a broad area. An aluminium alloy is particularly suitable here since in conjunction with conventional rollers of cargo drive units, this gives a good coefficient of friction. The core layer, which preferably connects directly to the seating layer, stiffens the entire construction and leads to substantial weight savings.
The seating layer can have a thickness of 0.5 mm to 2.5 mm, in particular 0.7 mm to 1.5 mm, in particular 0.9 mm to 1.5 mm. Preferably the seating layer has only a slight thickness in relation to the thickness of the entire cargo floor, e.g. less than 40%, in particular less than 30%, in particular less than 20% of the total thickness. To this extent, significantly lighter cargo floors can be produced.
The seating layer can have a strength of more than 400 N/mm2, in particular more than 500 N/mm2. To this extent the seating layer can protect the core layer from high spot loads. The cargo floor according to the invention wears only slowly under the usual rough handling, and is very robust.
It is possible to design the cargo floor in a laminated structure with only two layers. Preferably however a further layer, namely a wearing layer or top layer, can be provided which is arranged on the side of the seating layer facing away from the core layer.
The wearing layer can be made of metal alloy, in particular an aluminium alloy, and/or a glass fibre-reinforced plastic and/or a material from the group of aromatic polyamides (e.g. aramide). The wearing layer can protect the core layer from wear and stiffen the sandwich construction as a whole.
Said aluminium alloys for the seating layer and/or the wearing layer can be aluminium wrought alloys. The main alloy element used can be zinc, wherein zinc accounts for a proportion of 0.7 to 13%, in particular 0.8 to 12%. Such aluminium alloys are very hard. For example 7075 T6 or 7075 T7 can be used as a material.
Preferably the wearing layer is also connected to the core layer by form and/or material fit.
Said aluminium alloys can be aluminium alloys with a solution-hardened and/or thermally hardened and/or overhardened heat treatment, to ensure an adequate strength.
The core layer can have a thickness of at least 1 mm, in particular at least 1.5 mm, in particular at least 2 mm, in particular at least 4 mm, in particular at least 6 mm.
Preferably the core layer comprises a solid core. According to the application, a solid core is a core which is substantially solid. This means that the core layer comprises at least 50%, in particular at least 70%, in particular at least 90% carbon-fibre-reinforced and/or glass-fibre-reinforced plastic. There are no large cohesive cavities, in particular honeycomb structures or similar.
The wearing layer can have a thickness of 0.1 mm to 1 mm, in particular 0.2 mm to 0.6 mm, in particular 0.25 mm to 0.5 mm.
Preferably at least one wall has, at least in portions, an in particular rounded bead on its edge for fixing the wall to at least one profile element. As a result, a connection to the profile element or one of the profile elements can be achieved particularly easily, in that for example the bead is inserted in a (round) groove of the profile element.
At least one wall, in particular the bottom wall, can be bent inwards on at least one edge region. In an embodiment of the cargo holding device as a pallet, “inwards” can mean that the bend is oriented in the direction of a cargo holding surface. For a container, “inwards” can mean that the bend is oriented in the direction of a middle of the cargo holding space. In any case, as a result (in particular in combination with a round bead on the edge of a wall) a stable and in particular form-fit structure of the wall, in particular the bottom, can be achieved. The material usage is here particularly low.
At least one wall can have at least two layers of fibre-reinforced plastic, wherein a lay angle of a first layer is offset to a lay angle of a second layer by at least 30° and/or maximum 90°, in particular by 45° or 90°.
At least one wall can comprise at least one first layer with (exclusively) 0°/90° layers and at least one second layer arranged on the first layer with (exclusively) −45°/+45° layers. Reference is made here to a predefined longitudinal edge of the cargo holding device. Because of the two layers, it is possible to achieve easily both stabilisation in a corner region (by the −45°/+45° layers) and a stable fixing to the profile elements running for example along the edge (by the 0°/90° layers).
At least one wall can be made at least in portions from glass-fibre-reinforced plastic and/or carbon-fibre-reinforced plastic and/or aramide and/or Kevlar.
Preferably aramide/Kevlar is used in particular to improve the handling for example with forklift trucks. Alternatively, a film could be drawn over (conventional) cargo holding walls or pallets, on the outside of the cargo holding device. A thin outer layer can be introduced (on production of the walls) (for example as a further layer). In a refinement, the cargo holding device or pallet can be designed to reflect sunlight (without a protective sleeve necessarily having to be provided). A sunlight-reflecting layer can therefore be used instead of a protective sleeve. This is advantageous insofar as protective sleeves can often only be used once in the prior art, since they are damaged after first use (for example holes are created etc.).
At least one edge bead can be formed by a rod integrated into the edge, in particular a rod made of fibre-reinforced plastic, such as glass-fibre-reinforced plastic or carbon-fibre-reinforced plastic. Thus a connection to a fixing device of a profile element can be achieved in a simple manner.
Preferably at least one wall is attached to a/the frame of the cargo holding device via at least one corner plate, wherein the corner plate has preferably at least one bore, in particular a bore at least partly lined together with the wall. Further preferably, at least one in particular tarpaulin-like wall is attached to a frame of the cargo holding device via at least one plate, wherein the plate preferably has at least one bore, wherein further preferably at least one layer of the in particular tarpaulin-like wall is pressed into the bore. Thus with a suitable fixing means with preferably cylindrical cross-section, for example a bolt, a simple and secure fixing can be ensured of the in particular tarpaulin-like wall. For this it is furthermore advantageous if the fixing means has a flange portion. The in particular tarpaulin-like wall can be clamped between this flange portion and the profile element, further improving the stability.
The plate can be arranged at least in portions inside the wall and preferably be tapered in the direction of the wall centre. This gives a comparatively homogeneous transition region from the plate to the in particular tarpaulin-like wall (in the region in which this is not connected to the plate). This further improves the stability of the fixing. The weight is reduced.
The object cited above is also achieved, according to a refinement of the method described above (which also constitutes an independent aspect and is claimed as such), with a method for production of a cargo holding device, in particular of the type described above, comprising at least one profile element, wherein the profile element is made at least in portions by pultrusion of fibre-reinforced plastic. With regard to the advantages of the method, reference is made to the cargo holding device described above. A central advantage of this method is the possibility of producing cargo holding devices with substantially reduced own weight.
At least one wall of the cargo holding device can be made from an in particular tarpaulin-like, fibre-reinforced plastic, wherein the wall can be pressed in portions into a bore of the fixing plate, preferably using a tool with a conical portion. Thus the wall of fibre-reinforced plastic can be fixed to the profile element particularly securely.
Preferably the production method comprises production of a groove on the at least one profile element, preferably by pultrusion, and connection of the at least one wall to the at least one profile element by the introduction of a bead-like portion of the wall into the groove.
In a preferred embodiment, the production method comprises a push-fit connection of a plurality of profile elements to create a frame, in particular using corner elements.
Preferably the frame is pretensioned by attachment of a/the wall to the frame.
The object cited above is furthermore achieved independently by the use of a pultruded profile element of fibre-reinforced plastic for the production of a cargo holding device, in particular of the type described above.
The present cargo holding device requires no metal components at all. In a concrete embodiment, the cargo holding device can comprise an electromagnetic transmitter and/or receiver, in particular an RFID chip. Thanks to the absence of metal components, or at least a reduction in the proportion of metal components, this electromagnetic receiver and/or transmitter device can communicate particularly easily with a corresponding external transmitter or receiver. Interference by metal components is avoided or at least reduced.
As a whole, due to the special construction of the cargo holding device, the weight is reduced further significantly in comparison with known cargo holding devices. A weight reduction of 35% or more appears possible, which for example in the case of a Boeing 747 could be around 640 kg per total load weight in comparison with loading with known containers. If we assume that a Boeing 747 with maximum load consists of around one-third aircraft, one-third passengers or freight, and around one-third fuel, and in this form has a take-off weight of around 408 tonnes, the result is that around 130 tonnes of fuel are required to transport 272 tonnes of aircraft and load. With the cargo holding device according to the invention, in such a case around 320 kg fuel can be saved on each flight. As a result, the CO2 emissions can be further reduced substantially.
The term “side wall” can also mean a top wall (e.g. cover element) or a wall which is oriented upwards, or parallel or inclined in relation to the bottom element.